So I just bought an Estate Junior Heatrola stove and I'm not sure how to go about setting up the stove pipe. It's going in my garage which currently has no stove or chimney. I don't think I'll have any issues setting up the main part of the stove pipe and running it out through the garage, but I can't find any pipe that will connect to the oval opening on top of the stove, as it has some irregular measurements. As you can see in the photos, it's close to 8 1/2 by 4 1/4, does anyone know where I can find something that will fit?